It is the purpose of this research project to use the technology of electron microscopy to study the structure and synthesis of serum lipoproteins. Normal isolated serum lipoproteins, lipoproteins from certain types of lipid dysfunctions and lipoprotein models are under investigation. Structural studies on normal lipoproteins involve the use of more recent electron microscopic methods of analyzing molecular structure; this includes studies employing minimal beam exposure and electron diffraction. Investigations are also being carried out on abnormal lipoprotein particles from such diseases as familial lecithin: cholesterol acyltransferase deficiency, obstructive jaundice and Tangier disease. Ultracentrifugally isolated lipoprotein classes from these various types of lipid dysfunctions will be examined in the electron microscope and analyzed in conjunction with chemical and flotation properties. Efforts to normalize the abnormal lipoprotein structures noted in these diseases are also continuing in an attempt to better understand the structure and metabolism of normal serum lipoproteins. Studies on protein-lipid interactions of lipoproteins will also continue with particular emphasis on the interaction of very low density and high density lipoprotein apoproteins with polar and nonpolar lipids. Various lipoprotein products isolated at densities corresponding to very low, low, and high density lipoproteins are to be morphologically and chemically analyzed. The effectiveness of sonic radiation versus incubation or use of amphiphats in initiating protein- lipid complex formation will be particularly scrutinized.